The Loss-of-Fluid Test (LOFT) facility is a 50-MW(t) pressurized water reactor (PWR) system with extensive instrumentation to measure the thermal-hydraulic conditions during the experiments. The primary system operating fluid conditions of the LOFT system are typical of large [~ 3500 MW(t)], commercial PWR operations.

Experiment L8-2 is the second experiment in the LOFT Severe Core Transient Experiment Series L8, and was designed to evaluate the effect of primary coolant pump restart on core cooling when the primary coolant system (PCS) is highly voided of liquid.

The accumulator and low-pressure injection system were not allowed to inject fluid into the PCS until after core uncovery has occurred and the PCS pumps had been restarted. PCS pump restart did not produce a moderation in the core thermal transient, and Accumulator A flow was unblocked by the operator at a preselected temperature. All plant protective systems were triggered automatically shortly thereafter, followed by a rapid reflood of the PCS.